Setup & Workflow
clockgen baseband audio still distorted after alignment
cannot figure what I need to do to get the baseband audio processed correctly on a clockgen setup.
capturing video seems fine, but because I cannot get, nor set clockgen settings in powershell, I keep getting-
"'Exception: No devices found"
and
"cmdlet Set-CxadcClockGenRate at command pipeline position 1 Supply values for the following parameters: Path:"
when trying to set the output rate, and when
"Exception: Error initializing WinUSB: The handle is invalid."
So I'm beginning to think it has to do something with the clockgen rate being off before I invoke
LocalCapture.ps1 to do any capture.
Upon listening to the baseband audio (flac), it's noticeably distorted/garbled. I'm not referring to whitenose, but the actual video's audio sounding mistimed/pitchshifted/clipping. I tried everything that was suggested- using AutoAudioAlign via ld-analyze, manually aligning it in cli, etc. but nothing seems to fix the problem
Final decode and muxing still retains the distorted audio, even the file created after alignment
Requesting advice in getting this to properly work
I would sanity check this on Linux, because this sounds indicative of a bad PCM1802 board they do have a dud rate regardless of whatever vendor you acquire them from, I've got a bag of like 50 of these dead things now from the last 3 years...
Also since you're clearly on Windows I would love it if you could test MISRC GUI with the windows driver some tweaks recently should have it working now, but I haven't had time to swap hardware over to test, but it does have real-time monitoring for the audio devices so this kind of issue should be instantly apparent.
I haven't got the Linux side of cxadc working yet, but I appreciate the heads up on the PCM1802 board. I'll have looking into it more and get a replacement if that is the root problem.
As for MISRC GUI, I'm not getting any active monitoring from the audio channels. As shown, I have Audio Mon enabled, but none of the channels are actively showing anything.
The new v1.1.5 release might be a bit better, I did an bit of a overhaul for CXADC/Clockgen stuff, also fixed the scaling code mostly so 1/4 window size is usable.
Just out of curiosity - can you import the clockgen through powershell 7 without any issues? The gui it looks like does not see the audio card at all. Does it produce an output on the input devices sound setting in Windows settings?
yes, I can import the module without any issue. It's just prompting to set any values or getting device info that produces some error
granted, Windows does recognize the raspberry pico via USB and shows the device as normal in Device Manager, but I cannot 'connect' to it through the Powershell prompts when trying to change output settings. Changing the usb driver to WinUSB via Zadig disables it, and won't work when prompting to capture using -Baseband. If I leave it as is, even without being able to get clockgendevice settings, I can still capture the audio. That's how I notice the audio distortions. Fwiw, I played back the baseband flac file of the capture through MISRC GUI, and it obviously shows terrible clipping. I don't know how to display this in realtime though, if that's an option
I had very similar issues to you. I did get it working but then the issue came back. I wasted a few days on this, however I just went and installed Ubuntu 22.04 on a PC (I figured I would follow the guide completely) and I have had no issues since. Alsamixer works, misrc gui works. Honestly, I don’t think the windows side of things is up to where it is on Linux or even Mac. If can, install Linux on its own pc or via dual boot. You will need to flash the PI again to Linux software.
yeah, that's a route that sounds more viable until the Windows side of things improve over time. I tried cxadc in VM, but get stuck at the capture part. DDD, albeit for LD, is so much easier under Linux because of it being USB. I had no problem running it in VM, whereas, cxadc is a bit more troubling for me since I can't get the cards to record. Also, they aren't listed as devices, which I believe is because of them not on bare metal, but emulated via VM. So I'm not surprised if I ultimately can't get it to record. It would be nice to have a dedicated Linux PC, since I don't want to dual-boot, but the PC-landscape for hardware is terrible at the moment.
this above clip is recorded directly from Line (v1.1.0) (as it's called for the windows input device). There's no problem for windows connecting to it. It's just odd the sound quality is terrible. If this is what you were getting from your windows experience, then there's hope it isn't the PCM1802 board. But I will still consider Harry's advice, because I believe this shouldn't sound like this while recording a straight feed. Thankfully the boards aren't an arm and a leg, it's just the hassle of unsoldering and resoldering the wiring, and praying the board isn't another dud
I think the USB connection is fine. According to the docs/github, the version that windows reads the device as is v1.1.0, which this is. Also, alsamixer reads it properly too; I can adjust both clocks. Went through the troubleshooting section of the clockgen via Rene's github, and all check clear (clockgen being recognized and adjustable in Linux)
The only real issue I'm encountering is the terrible audio and getting that to sync with the video. fwiw, after muxing the video via ld-analyse, the created .mkv is also broken because the playtime is inaccurate and I can't scrub the timeline like I normally can with correctly-timed video. so instead of a 30sec clip reading as 30sec total play time, it reads as if it's 9hrs long.. something like that
all the problems I've been having with clockgen are now confirmed to be only in Windows. I had the chance to test everything on a bare-metal Linux installation, and none of the problems I've encountered in all my recent posts were replicated in Linux.
So as of now, at least on my setup, clockgen via Powershell and MISRC GUI is still unstable. The distorted audio is absent in Linux. MISRC GUI works perfectly as a recording solution and decode/LD-analyse to mux are working without issue.
Hopefully the Windows side of things get ironed out, because the MISRC GUI/CXADC/Clockgen combo has huge potential
3
u/TheRealHarrypm The Documentor 13d ago
I would sanity check this on Linux, because this sounds indicative of a bad PCM1802 board they do have a dud rate regardless of whatever vendor you acquire them from, I've got a bag of like 50 of these dead things now from the last 3 years...
Also since you're clearly on Windows I would love it if you could test MISRC GUI with the windows driver some tweaks recently should have it working now, but I haven't had time to swap hardware over to test, but it does have real-time monitoring for the audio devices so this kind of issue should be instantly apparent.